A Consumer Group Was Interested in Comparing the Operating Time

question 16

Multiple Choice

A consumer group was interested in comparing the operating time of cordless toothbrushes manufactured by two different companies. Group members took a random
Sample of 18 toothbrushes from Company A and 15 from Company B. Each was charged
Overnight and the number of hours of use before needing to be recharged was recorded.
Company A toothbrushes operated for an average of 119.7 hours with a standard deviation of 1.74 hours; Company B toothbrushes operated for an average of 120.6 hours with a standard deviation of 1.72 hours. Do these samples indicate that Company B toothbrushes operate more hours on average than Company A toothbrushes? The correct hypotheses to address this question are

• A) H0: µA - µB = 0 and HA: µA - µB < 0
• B) H0: µA - µB = 0 and HA: µA - µB ≠ 0.
• C) H0: µA - µB = 0 and HA: µA - µB > 0.
• D) H0: µA - µB > 0 and HA: µA - µB < 0.
• E) None of the above.

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Definitions:

Mycobacterium Tuberculosis

The bacterium that causes tuberculosis, a serious infectious disease affecting the lungs and potentially other parts of the body.

Respiratory Disease

A term for diseases that affect the lungs and other parts of the respiratory system, potentially leading to breathing problems.

Skin Disease

Any disorder that affects the skin's integrity or function, ranging from temporary, minor irritations to chronic conditions.

Bacteriophages

Viruses that infect and replicate within bacteria, often used in molecular biology and genetic engineering.